Phonographic sound box



D. A. SEALEY.

PHONOGRAPHIC SOUND BOX.

APPLICATION FILED JAN. 2!. I920.

Patented May 16, 1922" IL,%16,582n

gnvcwfoz DA 11. SEE. OF EAST GRANGE, NEW JERSEY.

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Application filed January 21, 1920. Serial lilo. 8,5259%.

T 0 a?! zrlzom 1'1 may concern:

Be it known that I. DAVID A. EALI-IY. a citizen of the Fnited States. residing at East Orange. in the county of Essex and State of New Jersey. have invented certain new and useful Improvements in Phonogiaphic Sound Boxes. of which thefollowing is a specification. reference being had to'the accompanying, drawings.

This invention relates to sound boxes. for phonographs or other sound recording or reproducing machines. and the general object of the invention is to provide a sound box so constructed that sound vibrations will be considerably amplified or rendered stronger. either when the sound box is used as a recording sound box or as a reproducing sound box. y

A further object in this connection is to provide a sound box which. by a suitable manipulation. can be caused to increase or decrease the sound reproduced.

A further objectis to provide a sound box having a pair of diaphragms. one of the diaphragms being connected to the recording or reproducing stylus carrying arm. as the case may be. and the other diaphragm being entirely free. the space-between said diaphragms being filled or partly filled with liquid. and provide means whereby the spa e between the diaphragms may be filled more or less full of liquid to thus modify the sound vibrations which are transmitted through the diaphragms and thus modify the sound reproduction or the recorded sound.

A further object is to provide a sound box of the character described with an air chamber providing for the outlet of air as the sound box is being filledwith liquid and providing. in effect. an air cushion against which the liquid in the sound box bears atall times.

A further object is to provide a connection to the sound box as described. a filling chamber adapted to be filled with liquid and having means whereby the liquid in said chamber may be forced into the sound box to more or les till the space between the diaphragms as may be desired.

Other objects will appear hereafter.

My invention is illustrated in the accompanying drawings. wherein Figure 1 is a front elevation of a sound box constructed in accordance with my in- Specifieation of Letters Patent.

Patented may 1M5. 1121322 illustrated in F igure 1. and this form of the sound box comprises an annular rim or body 10. which is angular in cross section. as illustrated particularly in Figure 2. Disposed against the base flange of this rim is a gasket 11. and against this gasket is disposed a diaphragm 12. This diaphragm may be made of metal. mica. glass ebonite or any other suitable material such as is commonly used in sound boxes today. Dis posed upon this diaphragm 12 is the annular and relatively thick gasket 13. and disposed against this gasket is the diaphragm l-l. which also may be made of any desired material. Against this diaphragm is .disposed a gasket 15. and bearing against this gasket is an annular plate 16 having a relatively thickened rim 1? which bears against the gasket 15 and against the rim of the manner. as by screws 18. 'll'heplate 16 is formed with the relatively thickened rim in order to space the body of the plate from the diaphragm 11 and to provide a resonating chamber around the margin of the diaphragm 11. It will be understood that the two mctions of the sound boxbody. the gaskets. and the diaphragms are to be held in close contiguity with each other so thatthe diaphragms will be securely clamped at their margins and will have liquid-tight engagement with the gaskets.

As illustrated in Figure 1. the upper portion of the wall of the sound box is provided with a globular chamber 19 connicating by a duct 20 with the interior of the space between the diaphragms 12 and 1 1. This duct 20 at its inner end is preferably flaringzand the wall of chamber 19 is pro vided with a relatively small bleed and preferably valved opening or vent 21.

While .1 may simply provide means for filling the space between the diaphra 'ms more or less era with liquid, r prefera bly body 10 and is held thereto in any suitable Mlii provide. as shown in Figure 1. a filling chamber 22 which. as illustrated in Figure 1,

is in the form of a cylinder. this filling chamber at its lower end being connected by a duct 23 with the interior of the sound box 'and being provided with a piston 2i operated by means of a screw-threaded stem 25 having a head atits outer end. This stem may be screw-threaded into the end of the cylinder. or the stem might have screwthreaded engagement with the piston. In

any event.'the stem is so mounted that a ro tation of the stem in one direction will cause the piston to move into the cylinder. forcing the contents of the cylinder out into the space between the diaphragms 12 and 1-1. and areverse movement of the piston will cause the liquid between the diaphragms to pass back into the cylinder 22.

I-do not wish to be limited to means for shifting this piston lon itudinally. I may. for instance. in place of the adjustable piston, as shown in Figure 3. use a flexible rubber tube 26 operatively connected to the space between the diaphragms. this tube being provided at its extremity with a ball 27 whereby a. compression of thebulb or ball 27 would cause liquid to be forced into the sound box, whereas an expansion of the bulb would. withdraw liquid from the sound box. Assuming that the sound box is provided with the cylinder :22 and the adjustable piston 21. it is obvious that if it is desired to fill the space between the diaphragms 12 and ll with liquid. the piston Qi is forced down in the cylinder '22 to its fullest ex-' tent and this will force all the liquid in the cylinder 22 into the space between the diaphragms and fill this space.

Inasmuch as the duct 20 is located at the uppermost portion of the sound box. it follows that any air within the sound box will be forced out through this duct and will not be trapped within the sound box. and preferably I so proportion the capacity of the sound box. that is the space between the two diaphragms and the cylinder :22. that upon a full depression of the piston the liquid will be forced up into the chamber 19 so as to prevent any inlet of air, and further form a static head. as it may be termed. which will compensate and permit the vibrations of the a mass of liquid.

Itwill be obvious that if the space between forced into the space under pressure. that the liquid being incompressible. there would be but little elasticity in the sound box butthatthe diaphra-gms would be forced outward away from each other with considerable force. By providing this globular chamber 1?, however. with its very small vent. I prov de for a certain amount of elasticity in the liquid even though the space between the dlaphragms is filled and the vent opening is the diaphragms was closed'and liquid was so small, being a mere pinhole. that while the air can escape, there is a certain amount of resistance to the passage of air so that the air in the upper portion 0t this chamber 19 acts elastically and exerts an elastic pressure upon the li uid when the diaphragms are vibrating an the li uid is vibrating.

Uf course. if it lJQ desired. as shown. to make the chamber 22 of less capacity than the sound box. a filling opening may be provided, closed by a screw plug 28. Thus. the space between the dia hragms may be normally partly filled with liquid and then a depression of the piston 2-l will cause sufi'e cient li uid to be forced into the space between t e dia hragms to entirely fill this space.

It is o v1ous. howe\ 'er, thatin the simplest-form of my invention the cylinder 22m n be omitted and the adjustment of the liquid within the space between the diaphragms be secured simply by filling this space more or less full through the opening normally closed ,by the plug :28 or emptying the liquid out to any desired amount through the opening and closing the opening again. By providin the cylinder 22. however. with the adj ustabIe piston thereon. I provide for a relatively delicate regulation of the sound box and of the sounds reproduced thereby. and it is obvious that where a bulb is used. as illustrated in Figure 3. the amoimt of liquid within the sound box can be constantly changed and thus the loudness or softness of the tone he constantly modified as may suit the operator.

In actual practice I fill. or partly fill. the space between the diaphragms with water. though it is obvious that other liquids such as glycerine or oil might be used and attain good results. I do not wish to be limited to a liquid. however. as I have found that a semi-liquid. as for instance. a jelly-like sub stance might. be used between the two diaphragms. this jelly-like substance constituting a body which is adapted to transmit elastic vibrations. I have found in actual practice. however. that the action of a liquid or semi-liquid disposed between the diaphragms is entirely dilferent from the action of a gas. such as air. between the diaphragms. A sound box having two diaphragms and with normal air pressure between the diaphragms will reproduce sounds but not very distinctly. As the air pressure between these diaphragms is increased. no dilference can be detected in the tone imtil the air pressure isconsiderable and suflicient to cause the diaphragms to bulge. At this point. the v tone produced appears to be very slightly deadened or muflled. though this deadening of the tone is fairly perceptible. and this deadening tone would seem to be caused by the highly compressed air. which actually prevents the diaphragms from vibrating and this interferes with. the quality of the music. 130

. softened until, when the sound box is entirely filled withliquid, the tone is the softest. I have found that mercury produces a fairly good tone and that the loudness and softness of the tone may be controlled, but on account of its excessive weight, mercury is not as practical as a liquid. such as water.

-A li uid or semi-liquid such as described may e forced to partly or entirely fill the space between the diaphragms or may be compressed to a greater or less extent by obvious means, such as the piston 24 shown in Figure 1, or an equivalent device.

I have found that a sound box constructed in accordance with my invention has many advantages over the ordinary sound box. It transmits or translates vibrations into sound or sound into vibrations much better than an ordinary sound box. When it is desired that the sound delivered by the sound box shall be particularly loud, then the space between the diaphragms is emptied of liquid or other material. When, however, it is desired that the sound shall be softened, the space between the diaphragms is more or less filled with liquid, depending upon the loudness of the sound desired, and this softens the sound without, however, causing any loss in the delicacy of the sounds or mufiling the tones. Thus, by the provision of the cylinder and piston described or equivalent devices. the sound box may be adjusted to suit any particular record or any particular condition of reproducing or recording. Of course, the sound box is to be provided with the usual stylus carrying arm a and stylus b, and it is obvious that the sound box may be used either with a laterally cut record or with a. hill and dale record, or for recording laterall records. In practice I find that it is best to space the diaphragms relatively close to each other but suificiently far from each other so that no capillary action will take place, as if the diaphragms are too near to each other, the liquid will not fill the space uniformly.

Preferably, though not necessarily, I prevent the passage of liquid through the vent 21 and thus prevent the passage of liquid out of the space between the diaphragms by means of a valve 29 constituting, in effect, a float valve. This valve may-be of any suitable design but, as shown, has a valve stem 30 which extends up through the vent opening but is relatively smaller than the vent opening and is supported in any cut or hill and dalesuitable spider 33 mounted upon the cham ber 19. This valve is preferably a fioat valve so that when the liquid rises in chamber 19 above a certain height, this valvewill close and prevent the escape of liquid. The function of this valve is to permit pressure to be applied to the liquid between the diaphragms 12 and 14:, as I find inL-actual practice that modulations of sound may be secured, not only by filling the sound box more or less full or liquid but by filling the sound box entirely full of liquid and then vary the pressure on this liquid by means of the piston 24 or by means of the bulb 27t I find, for instance, that the pitch of the reproduced sound may be gradually increased by allowing the water or other liquid between the diaphragms to be gradually withdrawn and that when the sound box is entirely full, if then the outward movement of liquid be prevented, as by the valve 29, and pressure be applied upon the liquid between the diaphragms. the loudness of the sound will be varied, the pressure applied upon the liquid tending to stiffen the diaphragms. Of course, I dp not wish to be limited to theuse of the valve 29 or to the position of this valve within the chamber 19, or to the use of this chamber 19 under all circumstances.

While I have illustrated certain forms of my device which I have found to be thoroughly effective in pracitice, yet I do not wish to be limited thereto, as it is obvious ..that many modifications might be made in the detailsof construction and arrangement of parts without departing from the spirit of my invention.

I claim 1. A phonographic sound box having a body, two diaphragms spaced from and disconnected from each other, the space between said diaphragms containing a liquid adapted to transmit the vibrations of one diaphragm to theother, and manually adjustable means permanently connected to the sound box for exerting more or less pressure on said material. 1

2. A phonographic sound box including a body, two parallel diaphragms spaced from each other and disposed a relatively short distance apart, the space between said diaphragms containing liquid, and manually operable means mounted upon the sound box and communicating with the space between the diaphragms for withdrawing liquid from between the diaphragms or forcing liquid thereinto.

3. A phonographic sound box including a body, two parallel diaphragms mounted upon the body and spaced from each other a relatively short distance, the space between said diaphragms containing liquid, a chamber mounted upon the body and having a vent opening and communicating opposite the vent opening with the space between the diaphragms, the sound box having means whereby liquid may be forced into the space between the diaphragms to fill said space and partly fill the said chamber.

4. A phonographic sound box having a body, two spaced diaphragms disconnected from each other, the peripheral wall of said space being provided with a duct leading therefrom, and a chamber into which said duct opens. the space between said diaphragms being filled with liquid, and manually operable means connected to the sound box and communicating with said space .whereby more or less liquid may be forced into said space or withdrawn therefrom.

5. A phonographic sound box having a body, two spaced diaphragms disconnected from each other, the peripheral wall of said space being provided with a duct leading therefrom, and a chamber into which said duct opens. the space between said diaphragms being filled with liquid, and means connected to the sound box and communicating with said space whereby more or less liquid may be forced into said space or withdrawn therefrom, said means comprising a cylinder, and a piston adjustable in the cylinder.

6. A phonographic sound box comprising an annular body, spaced parallel diaphragms disposed within said body, gaskets holding said diaphragms in spaced relation and supporting the margins of the diaphragms against the body,.means for clamping the diaphragms within the body. the peripheral wall of the box being provided with an outlet duct and an inlet duct, a chamber connected to the outlet duct and having a very small vent-opening, the outlet duct being disposed at the uppermost portion of the sound box, a cylinder connected to the inlet duct, a piston movable in said cylinder, and means for adjusting the piston at any desired position, said piston and the space between the diaphragms being adapted to be filled with liquid.

7. A phonographic sound box comprising a body, spaced diaphragms carried upon the g to the outlet duct and having a relatively small vent opening, and means mounted upon the sound box whereby liquid may be forced into the space between the diaphragms and into the chamber or withdrawn therefrom.

8. A phonographic sound box comprising a body, spaced diaphragms carried upon the body and disconnected from each other, the peripheral wall of the sound box between said diaphragms being provided with an outlet duct disposed at the uppermost portion of the sound box. a chamber connected to the outlet duct and having a relatively small vent opening, means mounted upon the sound box whereby liquid may be forced into the space between the diaphragms and into the chamber or withdrawn therefrom, and a float valve controlling the vent opening in the chamber and preventing the escape of liquid when the chamber is filled but permitting the inlet of air upon a reduction in the volume of liquid within the chamber.

9. A phonographic sound box comprising a body, spaced diaphragms disconnected from each other, means for forcing liquid into the space between the diaphragms or withdrawing it therefrom, and valves controlled means permitting the passage of air out of the space between the diaphragms when the amount of liquid between the diaphragms is increased but preventing the escape of liquid when the space between the diaphragms is filled with liquid and under pressure, said valve controlled means per? mitting the inlet of air when the amount of li uid between the diaphragms is decreased.

In testimony whereof I hereunto aflix my signature.

DAVID A. SEALEY. 

